Space discharge device



E. S. PURINGTON SPACE DISCHARGE DEVICE Apri1 22, 1941.

yFiled Jly 6, 1,939 ls sheets-sheet 1 GTON.

April 22, 1941. E; s. PURINGTON SPACE DISCHARGE DEvIE Filed July s, 1939 s sneet-sheet 2 M NNN\ ,l o .my 6 7 a a 3 w 8 8 l B/qul. 9 8 9 7 IHKII, V 8 5 7 9 0 oll OLV 9 e 9 m April 22, 1941 E. S. PURINGTON SPACE DISCHARGE DEVICE 3 Sheets-Sheet 5 Filed July e, 1939 Il l IIIIIIIII ...l

AMPLnFxER INVENTOR ELLISON 5. PURI NGTON.

. MncRoPHoNE'- of Flai;

Ellison S. Purlngton, Gloucester, Mass., assigner to .lohn Hays Haoud,

.'lr., Gloucester, Mass.

Application July 6', 1939, Serial No. 283,019 v (Cl. Z50-27.5) v

l claims. This invention relates to space discharge dei vices and more particularly to vacuum tube devices for operation at very high frequencies. The invention further relates to a vacuum tube device in which is incorporated two sets of electrodes which are connected in a substantially xed oscillatory circuit., c

The performance of a vvacuum tube with a given structure of cathode, grids and plate hitherto has been limited because of the inferior properties of the inductance circuit from plate to cathode through the plate lead, external lnnected to rods of filaments 21 and 28 ductor, external by-pass condenser andthe cathode lead.I

Y In the present invention, the .performance for a given structure of cathodes, lgrids and plates is very greatly improved -by designing the 'systemfor the specific frequencyfdesired, with substantially all the magnetic energy of the oscillatory circuit associated with a suitable coil-type inductor built within the tube itself. Preferemy e dual electronic structure is used, with push-pulloperation, and vwith the coil-type `inductor bridging between the plates of the two electronic structures. The inductor may be suitably center-1" tapped for plate power supply, and may be tapped for .connection to a low "impedance external transmission line. The plates may be provided l' with externalleads for connection to external impedances to provide for iine adjustment of the oscillatory circuit. f i

The invention also consists in original features of construction and combinations of parts' hereinafter set forth and claimed.

Although the novel features which are believed to be characteristicof this invention will be particularly pointed out in the claims appended hereto, the invention itself, as to its objects and ad- 4 vantages, the mode'of its operation and the manner of its organization may be7better understood byreferring to the following description, taken in connection with the accompanying drawings4 forming a part thereof, in which Fig. 1 is a longitudinal. sectional view illustrating the general structure of a' tube embodying the present invention; 2 is a transverse section taken online 2-2 Fig. 3 is a longitudinal section similar to Fig. l illustrating the Ageneral structure of a modified form of tube; .and

Fig. 4 illustrates diagrammatically a transmitting circuit including tubes of the types depicted in Figs. 1, 2 and 3'.

certain new and Y depicted in Fig. 3 a tube structure is shown which y respectively.

Like reference characters denote like parts in the several ngures of the drawings. Referring to the' accompanying more particularly to Figs. ture is shown which comprises a base II, a cap l2 and a tube I3 mounted between the base 'and the cap to form an envelope. Fused to the top and bottom of the tube I3 are pressesy I5 and I6 Mounted in the base II are six The prongs I8 and 2l are con- 25 and 26 which support the ends respectively. The other ends of the filaments 21 and 28 are supported by a branched rod 29. The rod -29 is connected to the prong 20. which is used as ground. 'I'he prongs 33 and 3|, supporting the rst grids 32 and-33 which surround the filaments 21 and 28 respectively. The second grids 35 and 36 are connected together and to a. rod 31 which in turn is connected to the prong I9. The third grids 38 and 39 are supported by the branched rod 29.- Condensers 40 and 4I are connected across the'filaments 21 and 26 and a. condenser 42 is connected between the grids 35 and 36 and the branched rod 29.

Mounted in' the cap l2 are four prongs 4.5-48.

drawings and prongs II-22.

` The prongs 45 and 48 are connected to rods 49 y and 5o. supporting cylindrical plates 6I and 62 which respectively surround the two sets of grids and filaments. Connecting the two plates 5I and 52 is a coil 53 the center point of which is con-l nected through a coil 55 to the second grids 3 5 and 36 and to the prong 31. The prongs 46 and Y' 41 are connected to rods 56 and 51 which in turn are connected to the coil 53 at suitable points.

The two 'sets'of electrodes are preferably arranged symmetrically within the casing and with respect to the connecting leads and prongs. More than two sets may be used in certain instances.

using a symmetrical arrangement. Suitable supporting members may be provided in addition to thoseshown but they should be of insulating material'so as not to aiect the operation o'f the tube. The conde'nsers 40, lll and 42 are also symmetri-v cally arranged and may be symmetrically located in the casing. They have been represented diagrammatic'ally for convenience.

The casing may be of metal, glass or-other l standard construction provided the "electrodes and leads are arranged generally as 'disclosed herein.

Referring tothemodified form oi the invention comprises a base 6I, a cap 62 and a; tube 63 mounted between the base4 and the cap. Fused l and 2, a tube struc- I1 and 22 are connected to rods |01. located suitably series.

ably magnetically coupled to `coil 93, and con- 'ergy is coupled from., the

' `pliiierV tubeV ||0 to the top and bottom of the tube 63 are glass presses 65 and 68 respectively. Mounted in the base 6| are four prongs 61-19. The prongs 81 and 10 are connected to rods 1| and 12 which support the ends of iilaments 'lfand 18 respectively, the other ends of which are supported by a branched rod 11. The Arod 11 is connected to the prong 69, whichis used -as ground. Surrounding the iilaments 15 and 18 are cylindrically shaped cathodes 18' and 19 respectively, which are supported from the branched rod 11. Mounted inthe cap 52 are iive prongs 80-84 The prongs 80 and 84 are respectively connected by rods 85 and 86 to cylindrical plates 81 and 88. The prongs 8| and 83 are respectively connected by rods 89 and 90vto grids 9| and 92 which surround the cathodes 18 and 19.

Connecting the two plates 81 and 88 is a coil 93. Mounted concentrically within the coil 93 but insulated therefrom is a second coil 95 the ends of which are connected respectively'to the rods 89 andV 90. The center point of the coil'95 is connectedb'y a rod 96 to the prong 82 and through a condenser 91 and a resistor 98 in parallel to the rod 11. 'I'he center point of the coil 93 is connected through a condenser 99 to the rod 11 andi through a rod |90 to the prong 58. Condensers and |02 are connected between the rods 1| and 12 respectively and the rod 11.

'Ihe tubes shown in Figs. 1-3 may be used in various high frequency circuits as oscillators or amplifiers. One circuit illustrating the use of such tubes is shown in Fig. 4. This circuit includes a master oscillator |05, a power amplifier |06 and a radiator 01. f

'I'he master oscillator |05 is shown as comprising a duo-triade tube |08, which may be of the type depicted in Fig. 3, the plates 81 and 88 of which are connected together through variable condensers |09. The power amplier is shown as comprising .a duo-pentode tube H0, which may be of the type illustrated in Figs. 1 and l2, the first grids 32 and 33 of which are connected to the grids 9| and 92 of the tube |08.

'I'he second grids 3 5 and 35 and the center 3f plate coil 53 of the tube l I0 are connected -through a transformer III to the output circuit of a modulator H2. Plate `power may be supplied by a source Illa. The input circuit of the modulator ||2 is connected to the output circuit of a speech -amplier H3 the input circuit of which is connected to a microphone AH5. The

plates 5| and 52 are connected together through H8.A Points on the coil a variable condenser are connected to the two arms of the antenna tant from tube H0.

power oscillator in conjunction with the Vernier condensers |09 generates the desired frequency, determinedv by 'the inductor element-93, and thecapacitor element comprising the two plate-cathode capacitances in series, bridged by the vernier condensers Ill in Thefeedbackisbythegridcoilsuitnected to the grids of the tube. Oscillatory enoscillator Ill to the ampliner'lll by dlrectconnection of grids" and l! of the-tube Ill'to grids and 3l of the.

tube un, bias mined by the |08. Plate for bothsets ot grids being detergrld circuit within tube power for the amfrom a common source including .the plate battery Illa and transformer III. lll is adjusted for best conversion` of this power to high frequency output power. Transformer serves to introduce modulatory energy from the modulator circuits ||2, actuated from speech' ampliiier H3, which in turn is actuated by microphone |I5. 'I'he output 'highfrequency oscillatory power is delivered from symmetrically located taps on coil 53', to a radiating system |01 comprising two quarter wave portions with the transmission line from coil 53 of well known proper length for best utilization of the ampliiied power produced by tube H0.

This speciiic circuit hasbeen shown only for `purposes of illustration. Other circuits could be readily devised, for example using a tube of the type H0 as a crystal controlled oscillator driving a similar tube'as a continuous wave telegraphic amplifier. By using suitably coordinated tubes of the general type indicated the construction of transmitters for very high frequency purposes may be made in a simple manner, with easy adjustment and with reliable circuit operation. The tube |08 may be designed to have a natural frequency just above the desired frequency, final adjustment to the desired frequency being obtained by the condensers |09.

A pair of sets of electrodes symmetrically arranged is suitable for push-pull operation or for operation in parallel. A single set of electrodes may be used, however, with the tuning coil connected fromplate to a by-pass condenser con.. nected to thecathode and all built within the envelope as above indicated. In general, the invention contemplates enclosing all possible tuning and connecting elements within the tube envelope and so mounting the same that all leads are maintained as short as possible. 'I'his is particularly important for very high frequencies to be limited to the specic embodiment shown Y herein. Various changes and modications may be made therein as will be apparent to a person skilled in the art. The invention is only to be limited inv accordance with the following claims.

-What is claimed is:

1. A space discharge device adapted for high frequency operation comprising an envelope havy ing a base member at .each end, a plurality of sets of electrodes disposed within the envelope, each s et comprising at least a cathode, grid and anode, an inducta'nce coil within the envelope interconnecting corresponding electrodes oi' said sets and forming with the interelectrode capacities an oscillatory circuit resonant approximately to the. 'operating frequency, terminal pins Acarried by each base member. connections from certain of the terminal pins of ,one base member to certain o1' the 'electrodes whereby energizing current and potentials may be'supplied thereto, a connection from another terminal pin o! said base member to the mid-tap on the inductance coiLsald last mentioned connection including a second coil,

-minal pins ot and connections-within the envelope to the terthe other base' member whereby the operating frequency may be supplied to an external utilization circuit. i

A anodes of said sets and 2. A space discharge device as deiined in claim 1 wherein each set of electrodes includes a. screen grid, and connections from said screen grids-to that end of the second coil to'which the terminal pin is connected. I

3. A space discharge device adapted for high frequency operation comprising an envelope having a base. member at each end, a plurality of sets of electrodes disposed within the envelope,

eachset comprising at least a cathode, a signal grid, a screen grid and an anode, an inductance coil Within the envelope interconnecting the' forming Withrthe intereiectrode capacities an oscillatory circuit vresonant approximately to the operating frequency, terminal pins carried by eachv base member, a connection from 'each signal grid to its respec-v tive terminal pin oi one base member. the screen grids being connected together and to ,another terminal pin of said one base member, a coll con'- nected between said common connection and thev mid-tap on the inductance coil, and connections separate cathode connection and the common cathode connection .and between the common screen grid connection and the common cathode connection.

ELLISON S. PURINGTON. 

